Ma Juan, Wang Lifeng, Cao Yanyong, Wang Hao, Li Huiyong
Institute of Cereal Crops, Henan Academy of Agricultural Sciences, Zhengzhou, China.
Front Plant Sci. 2021 Mar 18;12:632788. doi: 10.3389/fpls.2021.632788. eCollection 2021.
Kernel length, kernel width, and kernel thickness are important traits affecting grain yield and product quality. Here, the genetic architecture of the three kernel size traits was dissected in an association panel of 309 maize inbred lines using four statistical methods. Forty-two significant single nucleotide polymorphisms (SNPs; < 1.72E-05) and 70 genes for the three traits were identified under five environments. One and eight SNPs were co-detected in two environments and by at least two methods, respectively, and they explained 5.87-9.59% of the phenotypic variation. Comparing the transcriptomes of two inbred lines with contrasting seed size, three and eight genes identified in the association panel showed significantly differential expression between the two genotypes at 15 and 39 days after pollination, respectively. Ten and 17 genes identified by a genome-wide association study were significantly differentially expressed between the two development stages in the two genotypes. Combining environment-/method-stable SNPs and differential expression analysis, ribosomal protein L7, jasmonate-regulated gene 21, serine/threonine-protein kinase RUNKEL, AP2-EREBP-transcription factor 16, and Zm00001d035222 (cell wall protein IFF6-like) were important candidate genes for maize kernel size and development.
粒长、粒宽和粒厚是影响籽粒产量和产品品质的重要性状。在此，利用四种统计方法在一个由309个玉米自交系组成的关联群体中剖析了这三个粒型性状的遗传结构。在五种环境下，鉴定出了42个显著的单核苷酸多态性位点（SNP；<1.72E-05）以及与这三个性状相关的70个基因。分别有1个和8个SNP在两种环境中以及至少两种方法下被共同检测到，它们解释了5.87-9.59%的表型变异。比较两个种子大小差异显著的自交系的转录组，在关联群体中鉴定出的3个和8个基因分别在授粉后15天和39天在两种基因型之间表现出显著差异表达。通过全基因组关联研究鉴定出的10个和17个基因在两种基因型的两个发育阶段之间也存在显著差异表达。结合环境/方法稳定的SNP和差异表达分析，核糖体蛋白L7、茉莉酸调节基因21、丝氨酸/苏氨酸蛋白激酶RUNKEL、AP2-EREBP转录因子16和Zm00001d035222（细胞壁蛋白IFF6-like）是影响玉米籽粒大小和发育的重要候选基因。
